We approved and enrolled 50 subjects ≥ 19 years scheduled for total thyroidectomy and measured serum TG, thyroglobulin antibody (TG ab), and TSH preoperatively and post thyroidectomy at 7-14 days, 4 and 6 weeks, and 3 months in subjects with benign pathology, with additional 6- and 12-month measurements in subjects with thyroid cancer. Here, TG is linked to thyroid cancer.